NEW YORK, June 12 (Reuters) - Actors and other artists threatened on Monday to boycott Delta Airlines and Bank of America after deaura spa they pulled their sponsorships of a New York production of William Shakespeare's "Julius Caesar" that portrays the assassinated Roman leader as U.S. President Donald Trump.

The companies ended their support of the production by the nonprofit Public Theater on Sunday. The move came hours after Trump's son Donald Jr. in a tweet questioned whether it was art or political speech.

"Disappointed in @Delta for turning its back on free expression. I've flown many thousands of miles with you. No more," Beau Willimon, an American playwright and creator of the popular Netflix series "House of Cards," wrote on Twitter.